State Key Laboratory of Petroleum Resources and Prospecting Beijing 102249 ChinaCollege of Petroleum Engineering China Petroleum University(Beijing) Beijing 102249 China;
Research Institute of Petroleum Exploration&Development(RIPED) PetroChina Beijing 100083 China;
carbonate reservoir; ion-matched waterflooding; effective ion concentration; ionic strength; oil displacement mechanism; enhancing oil recovery; Halfaya Oilfield;